The race for the makeup Oscar is a noteworthy study in contrasts: The fantastical characters for the most successful franchise in movie history, recreating Margaret Thatcher, the most powerful woman of the 20th century, and a creative exercise in gender-bending. Of course, “The Iron Lady” and “Albert Nobbs” have the added advantage of boasting best actress nominations for Meryl Streep and Glenn Close and supporting honors for Janet McTeer. There’s just no denying the effectiveness of the makeup in making us believe that Streep is the dynamic and divisive Thatcher and that Close and McTeer are men in disguise looking for better lives in 19th century Dublin.

Then again, the temptation to honor the considerable below-the-line achievements in “Harry Potter” might be too strong for Academy voters to resist. And there’s even more detailed craft that went into bringing J.K. Rowling’s imaginative beings to life in the “Deathly Hallows — Part 2” finale.

“Because it was the last film, we had the opportunity to revisit every technique and see if we could improve it,” suggests Nick Dudman, who’s nominated along with Amanda Knight and Lisa Tomblin. “So with the Goblins from the first movie, we revisited the materials and looked at how to approach it. We decided that all the prosthetic makeup would be foreground so that [director] David Yates could film with any group of Goblins anywhere, anyhow. And it would all be for close-ups. So for 40 different characters there was a separate life cast, a separate sculpt, separate purpose-made wig; everything was pre-painted. Everything would be punched one hair at a time for everyday shooting. But it’s a serious commitment of manpower because you’re running a factory to mass produce everything. We brought people in from all over Europe that we encountered at trade shows and trained them to just do that makeup.”

Then there was the tweaking of the villainous Voldemort (portrayed by Ralph Fiennes). He makes for a gruesome image as a result of his digitally removed nose. “He’s wearing prosthetic forehead pieces to take out his eyebrows and he’s covered in transfer tattoos of all his veining; and he’s uncolored down; he’s got nails and teeth and stitched up completely,” Dudman continues. “How could we improve Voldemort’s tattoos; how could we make Dumbledore’s brother, Aberforth [Ciaran Hinds] look like Michael Gambon; and then we had the aging makeup of the kids at the end, which was one of the hardest challenges.”

Indeed, the aging of Harry (Daniel Radcliffe), Hermione (Emma Watson), and Ron (Rupert Grint) is the icing on the cake, as it were. Having pushed the makeup too far, they actually had to shoot the sequence twice and pull back some. “We went for minimal prosthetics around the eyes and color and changing texture and they’re in body suits to make the girls curvier and the guys stockier. If you looked at what we did in isolation, you wouldn’t notice much. It was the overall effect. They did go in and digitally enlarged the earlobes in post. But it’s 19 years later and it’s such a jump from the kids on the bridge at the end of the battle. You mustn’t distract the audience.”

Ironically, in a nice bit of symmetry, both the first and last scenes that Dudman worked on were the kids catching the Hogwarts Express at the railway station. “The thing about ‘Potter’ we’ve always said is: You’ve got to treat it as though it isn’t a fantasy film at all — you’ve got to treat it like everyone’s got a history they’ve lived through and it has a reality to it. So we really did obsess on detail.”

With “The Iron Lady,” Mark Coulier (who also helped apply the Voldemort makeup) and his team was tasked with recreating Thatcher at two different ages: her prime as Prime Minister in middle age and as an elderly 86-year-old living alone in her apartment.

“For the younger age, the one thing that Thatcher had was a strong brow ridge at the top of her nose that Meryl doesn’t have, and her dentures to push her mouth out a little bit,” Coulier explains. “We thought that with the wig and the costume and Meryl’s performance, that was enough for the younger age. For the older, we pushed it a little further: we injected more of the puffy cheeks that Thatcher developed in later years and the neck. We were really able to duplicate Thatcher’s neck completely and transpose that onto Meryl. And then obviously the wigs changed. Meryl’s personal makeup artist, J. Roy Helland [a co-nominee] handled all the wigs and created the makeup. He shaded her eyes using eye shadow and powders; he helped us create that sort of hooded, livid look that Thatcher had. And then Meryl adopted the mannerisms and movements of Thatcher that helped create the image of the makeup and the performance working together. ”

The challenge of the younger age was making a standalone piece in the center between the eyes and the top of the nose disappear. “It’s really a focal point with huge close-ups,” Coulier adds. “And it’s quite a difficult place to have a piece and blend it. It was a tricky prosthetic. And then the older stage was just dealing with making a new set of pieces for every day. So we had 23 sets of neck and cheeks and every appliance that we used. Sticking it on and having it filmable in close-up for 12 hours.”

Meanwhile, “Albert Nobbs” posed a host of tricky challenges, and like Streep with Thatcher, Close and McTeer were very involved in the design and execution of their looks. It’s a testament to the effectiveness that all three actresses were nominated for their performances.

“It was all about taking these two beautiful women and turning them into men,” explains Matthew Mungle, “trying to figure out what’s going to make them look like masculine women. Because it was set at that time, that helped us tremendously. Glenn’s look in the initial test was a little harsher than it ended up being. She had a picture of a Bosnian woman that looked like a man. She wanted that dark look. We had light brown contacts on Janet but we put Glenn in brown contacts and once the film was picked up she decided to soften Albert’s whole look beginning with her blue eyes. The nose was a different shape and we lightened the hair. I also recommended to Glenn that we push her ears out to give her more of an endearing quality, which she loved.”

For Hubert, the painter, McTeer recommended a broken nose to convey the spousal abuse the character endured. And so Mungle introduced some veneers on her teeth to make it look like she had a chipped tooth. He also sculpted their noses. At the same time, co-nominee Martial Corneville remade wigs in keeping with revised looks for both characters. Director Rodrigo Garcia wanted Hubert’s skin rougher than Albert’s; then Close wanted a new nose and recommended that they duplicate husband David Shaw’s. Co-nominee Lynn Johnston applied the prosthetics and key makeup.

“I don’t like to put too much prosthetics on characters like this so I played with filling both Janet and Glenn’s faces out,” Mungle continues. “I always try to do it from within inside. I always like a less is more approach.”

Sounds like all three nominees have something in common in conveying the proper physicality to help achieve the desired dramatic impact.